LumaSense Technologies IN 6/78-L - Manual (Page 14)

IN 6/78-L Operating Manual Controls and Connections · 14
3.2 Connecting the pyrometer to a PC
The pyrometer is equipped with a RS485 serial interface. With the RS485, long transmission
distances can be realized and the transmission is, to a large extent, free of problems. The RS485
also allows several pyrometers to be connected in a bus system.
If a RS485 connection is not available at the PC, it can be accomplished using the RS485 to USB
connector. When using a RS485 to USB adapter, make sure that the adapter is fast enough to
receive the pyrometer’s answer to an instruction of the master. Most of the commonly used
adapters are too slow for fast measuring equipment, so it is recommended to use the
RS485 ó USB converter “USB nano“ (ref. no. 3 826 720).
3.2.1 Connecting to RS485 interface / baudrate
Half-duplex mode: A1 and A2 as
well as B1 and B2 are bridged in
the 12-pin round connector of
the connecting cable, to prevent
reflections due to long stubs. It
also safeguards against the
interruption of the RS485 Bus
system should a connecting plug
be pulled out. The master labels
mark the connections on the
RS485 converter. The maximum
transmission rate of the serial
interface in Baud (Bd) is
dependent on the length of the
cable. Values between 1200 and
115000 Bd may be set.
The baud rate has to be reduced by
50% when the transmission distance is doubled (see 4.7 Baud rate). Typical cable length for
19200 Bd is 2 km.
3.2.2 Connecting additional analyzing devices
Additional analyzing instruments, such as a LED digital display instrument, need to be connected
to a power supply and the analog outputs from the pyrometer. Other instruments, like a
controller or printer, can be connected to the display in series as shown below (total load of
resistance max. 500 Ohm).
yellow
LED digital display
Controller
Power supply
green
brown
white 230V ~
24 V DC
°C
Writer